Coral biologist Dr Neal Cantin said: “We travelled to 14 reefs between Townsville and Cairns, including Fitzroy Island where we saw surviving coral producing eggs, which was not expected at all.

“Previous studies have shown a two to three year delay in reproduction after severe bleaching but at most of the reefs we are finding colonies of Acropora [branching hard coral] colonies with early signs of egg development in shallow waters, 3m to 6m deep.”

Two successive mass bleaching events have decimated the reef; one occurred in 2016 and the other earlier this year.Source:AFP

The project’s team leader Dr Line Bay added, “The majority of coral colonies on the inshore reefs have regained their colour and the growth of some colonies was so good they had overgrown our original research tags.”

Sadly, it’s not all good news.

“Some of the more sensitive corals are now rare even in areas where they had been abundant in March,” Dr Cantin said.

The AIMS team will now test whether the eggs are able to be fertilised.

Coral spawning in action on the Great Barrier Reef.Source:News Limited

Great Barrier Reef coral spawning viewed from the air.Source:News Limited

“There is concern the eggs may not be able to successfully fertilise and develop into coral larvae,” Dr Cantin said.

“The eggs are now white, and just before the spawning event they should turn pink when they are preparing for the spawning.”

The annual spawning event is due on the full moon of December 5. Dr Cantin said each coral could produce eight to 12 eggs per polyp in colonies of thousands of connected polyps.

While this is welcome news, the reef still has a long road to recovery.

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